           (async/onto-chan to-assoc-ch nblbs)
           ;; NOTE: we do out of order processing to speed things up here.
           (async/pipeline-async
-           100 assoced-ch
+           50 assoced-ch
            (fn [to-fetch ch]
              (go-try S
                (debug {:event :bassoc-in :id to-fetch})

                                      (:crdt downstream)))
              ncs (<? S (-missing-commits crdt S cold-store out fetched-ch
                                          (:op downstream)))
              max-commits 10000]
          (info {:event :fetching-new-values
                 :pub-id (:id m) :crdt [user crdt-id]
                 :remote-peer (:sender m) :new-commit-count (count ncs)})


;; TODO
;; decouple fetch processes of different [user crdt-id] pairs.

;; WIP size-limited buffer:
;; maximum blob size 2 MiB
